Friction let-off for looms.



. LACEY.

FRICTION LET-OFF FOR LOOMS.

APPLICATION FILED MAR. l?. 1915.

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Patented Mar. 19, 1918.

F. LACEY.

FRICTION LET-OFF FOR LOOMS.

APPLICATfoN FILED MAR` 17. 1915.

1,260,272. Patented Mar. 19, 1918.

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FRICTION LET-OFF FOR LOOMS,

APPLICATION FILED MAR. I7. 1915.

1,260,272. Patented Mar. 19,41918.

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FRlcTloN LEY OFF FOR Looms APPLICATION FILED MAR. I7. 1915: 1,260,272.

Patented Mar. 19, 1918.

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FRICTION LET-OFF FOR LOOMS.

APPLICATION FILED MAR. 17.1915. 1,260,272. Patented Mar.19,1918.

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FRICTION LET0FF FOR LOOMS.

APPLICATION HLED 1111111.17. 1915.

1,260,272. Patented Mar. 19,1918.

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F. LACEY.

FRICTION LET-OFF FOR LOOMS.

APPLICATION FILED MAR.17.1915.

1,260,272. .Patented Mar. 19, 1918.

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F. LACEY.

FRICTION LET-OFF FDR LOOIVIS.

APPLICATION FILED MAR. II. i915.

1,260,272. 19316111611 Mar. 19, 1918.

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F. LAC EY.

FRICTION LET-OFF FOR LOOMS.

APPLICATION FILED IIIIIII` II. 1915.

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FRICTION LET-OFF FOR LOOMS.

APPLICATION FILED MAR. 17. 1915. 1,260,272. Patented Mar.19,1918.

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FRICTION LET-OFF FOR LOOIWS.

To all whom t may concern.'

-Be it known that I, FRED LACEY, a citizen of the United States, residing at Lowell, in the county of Middlesex, State of Massachusetts, have invented a certain new and useful Improvement in Friction Let-Offs' for Looms, of which the following 'is a specification, reference being had therein to the accompanying drawings.

The invention comprises improvements 1n spring-actuated friction let oifs7 for employment more particularly 1n connectlon with the warp-beams of looms, although not necessarily restricted thereto. l

Weightactuated friction let.- offs are in general use in weaving, and Sprlng-actuated friction let-offs are more or less known, although not in extensive use. The action of let-offs of both of such classes is to apply friction in connection with a warp-beam in a loom s0 as to oppose the turmng of said beam, and through the frictional retardation control the unwinding of the warp by pull exerted on the latter, so that the warp shall be maintained under tension suitable for the weaving, and shall be permitted to unwind from the beam only at the rate required by the rate at which the warp is woven into cloth and the cloth drawn forward by the take-up mechanism of the loom.

During weaving, the warp in a lloom is subjected to intermittent strains, some of which are due to the movements of the harness-frames in opening up sheds iny the warp for the passage of the shuttle, while others are due to the action of the lay and reed in ubeating-up the successive picks of weft. These strains tend to turn the warpbeam forward, and in the case of a loom employing a friction let-off they operate to draw the warp from the warp-beam at lthe rate required for the weaving operation, in proportion as the woven-cloth is taken up. Weight-actuated friction let-off devices in some instances have the advantage that such devices permit the warp-beam to turn forward `when the intermittent strains come, so that thereby such strains are accommodated, and then, Iwhen such strains cease, act to turn the warp-beam reversely suiiiciently to keep the warp-tension normal. The explanation of this reverse turning of the warpbeam is that in the forward turning move- Specification of Letters Patent.

Patented Mar. 19, 1918.

Application led March 17, 1915. Serial No. 15,049.

ment of the war -beam just referred to the beam-head or ru e, acting within the encircling portion of the frictionchain, acts through the said chain with a tendency to raise the weightlever and weight. When the intermittent strains. cease, the weight descends and in descending acts through the chain and the frictional engagement of the latter with the beam-head or ruiiie to turn the warp-beam reversely as far as permitted by the tension of the portion of warp .extending through to the woven cloth.

Weight actuated friction let oii" devices, however, presentv in their operation certain drawbacks. One of these is the fact that sometimes the forward rocking movement of the warp-beam acts through the chain to move the weight-lever so as to lift the weight suddenly, so that the quick rise of the latter, and the overthrow thereof due to momentum, relieve the chain more or less of the effect of the weight for the time being, so that the friction upon the beam-head or ruile is lessened, which allows the warpbeam to turn too easily under a Sudden strain occurring at such time, as for instance that dueto the beating-up operation. It will be understood that the said lifting of the weight-lever usually takes place as the shed is formed for the next iight of the shuttle. The effect of the beating-up of the preceding weft-shot just as an extra heavy shed is opened frequently is that the warpbeam is caused to jump forward and to slip relatively to the friction-chain, so that an unnecessary paying out of warp occurs and rowey goods are produced.

Some of the drawbacks of weightactuated friction let-oi's, including the foregoing, are due in large part to the fact that a weight is logy; that is to say, when employed 1n connection with a let-off lever it starts tardily, going up too late in yielding to increase of strain tending to draw the warps 0H the warp-beam, and going down too late when the strain ceases; When once started to going up, its effect as a frictionproducing means becomes diminished during the upward movement. In addition its inertia and momentum carry it beyond the point to. which it is actually necessary it should yield. Hence when a weighted letoif lever lifts suddenly it goes up too loosely.

An additional consequence ofthis last feature is that in dropping, thev weight-lever takes up the slack in the chain wlth a Jerk tending to Snap the warp yarns. The bad effects are particularly noticeable in Weaving the last cut from the warp-beam as the warp unwinds from a small dlameter.

Another drawback of a weightactuated friction let-oil' is the fact that for weaving some classes of goodsmore weights have to be hung upon a let-off lever than for weaving goods of other classes. When the additional weights are not needed the are taken away from the looms, and requlre to be stored; when needed again, they must be brought back to the looms. Thisentalls handling and transportation, in addition to the necessity for providingl storage accommodations. It happens sometimes that weights that have been removed from certain looms and taken away for` storage become misplaced and lost, or are applied to use on other looms, and consequently cannot be found or had when needed.

Spring-actuated friction let-offs have been used, but as heretofore constructed most of them have drawbacks and disadvantages equally as undesirable and inconvenient as those incident to weight-actuated let-offs.

Springs have advantages over weights.

vThey do not have the drawbacks incident to the inertia and momentum of weights. They respond quickly and lightly at first, their tension becoming progressively stronger.

The general aim of the invention is to provide spring-actuated friction let-off devices which shall be free from the drawbacks and disadvantages aforesaid of prior let-off devices of both of the named classes of let-offs. 'Another is to provide springactuated friction let-off devices which will compensate for varying strains by permitting forward rocking movement of the warp-beam to accommodate strains due to shedding and beating-up, and then as such strains lessen will act to rock the beam backwardly to take up slack and maintain uniformity of warp tension. More special aims of the invention are to provide for the employment of a spiral spring of considerable length, which i is important inasmuch as a long spring has greater resiliency than a short one. It also is less subject to breakage. Also, to permit the employment of a highly resilient spring, light and sensitive in respect of the lettingoff action. Also, to provide for a wide range of adjustment of the amount of friction.. Also2 to provide for readily throwing the friction off and on, and to produce devices which will enable. the friction to be restored just as it was prior to being thrown off. Also, to rovide for the friction being thrown clip and on again by the lfoot of the weaver while his hands are occupied with the beam or warps.

. tion in connection The drawings show various embodiments of the principles and features of the invention.

Figure 1, Sheet 1, is a rear elevation of a portion of a loom frame with a warp-beam and one embodiment of my invention mounted thereon, the parts being in working positions and relations.

Fig. 2 is a rear elevation with the warpbeam removed and the parts positioned as when the friction -is thrown ofi'.

Fig. 3 is a rear elevation showing a modi-l fcation of the stop for determining the working positions of thev parts.

r-Figs. 4 to 10, Sheet 2, are views of details of the embodiment shown in Figs. 1 and 2.

Fig. 11, Sheet 3, .is a rear elevation, and Fig. 12 is a partial plan, of the devices of Figs. -1 and 2 when arranged to apply fricwith one end only of the warp beam. l 1.`

Figs. 13, 14 and 15, Sheet 4, and Figs. 16 to 20, Sheet 5, show various embodiments of the invention having simple lever arrangements.

Figs. 21 and 22, Sheet 6, are views showing an embodiment having a compound lever arrangement.

Figs. 23 to 32, Sheet 7, are views of details lof the said compound lever arrangement.

Figs. 33 and 34, Sheet 6, show the compound lever arrangement of Figs. 21 to 32 adjusted to act with simple leverage.

Fig. 35 is a rear elevation showing an embodiment of the invention containing a contracting or pull-spring.

Fig. 36 is a sectional detail view on an enlarged scale showing more particularly the spring of Fig. 35 and the parts which in such view are most closely associated with the spring.

Fig. 37 is a rear elevation, warp-beam and chains, bodlment employing a spring.

Fig. 38 is a sectional detail view on enlarged scale showing the spring and associated parts of Fig. 37.

Figs. 39 to 42, inclusive, areviews of details of the embodiment shown in Figs. 37 and 38. v

Fig. 43 is a rear elevation, also omitting the warp-beam and chains, showing a further embodiment employing a contracting or pull-spring. i' Figs. 44, 45, 46, 47 aredetail views oh enlarged scale showing various forms of rods adapted to be employed `in connection with contracting or pull-springs.

Fig. 48 is a rear elevation similar to Figs. 37 and v43, but showing a further embodiment ofthe invention employing a contracting or pull-spring.

Fig. 49 is a sectional -fdetail view onenomitting the showing another emcontracting or pulllarged scale showing the spring and associated parts of Fig. 48. Figs. 50 and 51 show 'afurther embodiment containing an expansion spring; Figs. 52 and 53 show still another. Figs. 54, 55 and 56, Sheet 3, show an embodiment containing a modification of the means of connection between the swiveling collars 11V, 23V, and the let-oftI levers. D

In various views of the drawings, portions of the side-frames 1, 1, of a loom are represented, and in Fig. 1 and certain other Views a warp-beam 2' filled with warp is shown mounted by means of journals 3, 3, in bearings in the said side-frames. The cylindrical portions 4, 4, usually termed ruiies in connection with the heads of the said beam, are represented as having ordinary friction chains 5, 5, wrapped around the same in usual manner, each of the said chains having one end thereof engaged with the horns of a bracket 6 fixed upon the loom girth 19, and its other end engaged with a hook 7 applied to the horizontal arm of one of the let-0E levers 8. Each let-olf lever is shown pivoted by means of a fulcrum-pin or bolt 9 (see in particular, Fig. 7 upon the corresponding stand or bracket. 'One of the said brackets 6 is shown in detail in plan in Fig. 4, in rear elevation in Fig. 6, and in partly-sectional side elevation in Fig. 7.

One of the let-off levers is shown in detail in vertical section in Fig. 7 and in rear elevation in Fig. 8.

Having reference, first, to the embodiment shown in Figs. l and 2 and the accompanying detail views on Sheet 2 of certain of the features of the invention This embodiment contains certain of the generic features of the invention. It affords an example of the employment of the longitudinally expanding or push type of spiral spring, and illustrates a use of two springs and of two rods in connection therewith. Examples of the employment of the longitudinally contracting or pull type of spiral spring, and of single springs and single rods, are presented in other embodiments shown and described herein of the various features of the invention.

The two springs employed in this iirst embodiment for actuating the let-0H levers to tighten the friction chains around the heads or ruiles of the warp-beam are shown at 15, 15, there being one thereof adjacent either let-olf lever. As will be perceived, the said springs .are both of considerable length. The two rods employed in connection with such springs, and serving as supports and guides therefor, are shown at 12, 12. The inner ends of the said rods are joined together by a pivot 14. For convenience in making the joint, the said inner ends are provided with flat disk-shaped heads 13, 13, which it together side by side,

as shown more particularly in Figs. 4 and 5,

Sheet 2, which are plan and bottom views,

respectively, of the two rods and' some of the parts in connection therewith. The connecting pivotal bolt or pin 14 occupies central holes in the two flat heads. The outer portions of the rods pass through and project beyond collars or sleeves 11, 11, which are engaged with the downturned arms 10, 10, of the let-off levers. The fit of the rods within the said collars or sleeves '11, 11, is such as to permit sliding movement of the rods and said collars or ysleeves with relation to each other. The springs 15, 15, respectively, are mounted upon the respective rods 12, 12, and encircle the latter between the collars or sleeves 11, 11, and fixed collars 16, 16, with which the rods are provided. The are confined and compressed lengthwise etween said collars or sleeves 11, 11, and said ixed collars. Consequently, each spring acts expansively in one direction against the collar 16 of the rod encircled bysuch spring, and in the other direction against the collar or sleeve 11 through which such rod passes. By the pressure transmitted to the collars or sleeves 11, 11, the let-off levers are actuated. To provide for regulating the frictional resistance by which the turning of the warp-beam for the delivery of warp is controlled, the collar 16 of each rod is made adjustable along the rod toward and from the collar or sleeve 11, so as to enable the spring to be compressed more or less between them. For convenience in making the adjustment, the collar 16 in this instance is formed as a nut and screwed upon a threaded portion 12'd of the rod. as shown bestin Figs. 4 and 5. By being made of enlarged size and adapted to serve as a hand-wheel, the turning of collar 16 in making adjustments is facilitated. The construction of the collars or sleeves 11, 11, is shown more particularly in Fig. 9 of Sheet 2, which is a plan View partly in section on line 9, 9, of Fig. 7, and in Fig. 10, which is a front elevation of the parts shown in Fig. 9. Each collar or sleeve 11`is engaged with the corresponding let-olf lever with capacity to swivel relative thereto in a vertical plane.

It has been explained that the pressure of each spring 15, is partly exerted outwardly against the corresponding collar or sleeve 11, and partly inwardly against the corresponding collar 16. This inward pressure or reaction of each of the springs l5, 15, tends to push the corresponding rod away from the let-off lever with which it is combined, toward the opposite side of the loom, so as to transmit pressure to the let-ofi lever at that side of the lever also. As one result of this, when the rods are in the straight condition of Fig. 1 the combined power of the twosprings is exerted in tendthe bent or broken ing to swing the two let-olil levers in opposite dircctons with respect to each other. The two levers are acted upon with equal forcc,-so that, other conditions being equal, the friction at both ends of the warp-beam is equal. The effect is the same as though a. single spring were interposedV between the two levers, and in fact in some cases I omit one spring and lock the corresponding rod to its collar` or Sleeve 11 so as to prevent longitudinal movement of the rod with relation thereto.

As connected together pivotally at thelr inner ends and mounted at their outer ends in the collars or sleeves 11, 11, engaged wlth the let-oil' levers, the rods 12, 12, are adapted to occupy a practically straight posltion substantially in lin@l with each other as 1n Flg. 1, and also are adapted to be swung from such position into a position in whlch they are bent upward at an angle to each other as in Fig. 2. They form a toggle. In the practically, straight and extended condition of the said toggle represented in Fig. 1 the tension of the springs 15, 15, (or of the single spring when ne spring is omitted) is utilized to apply outwardly-acting pressure to members 11, 11, to actuate the let-olf levers to create the friction by which the turning of the warp-beam is controlled. In condition of the toggle represented in Fig. 2, the rods 12, 12, and their collars 16, 16, are drawn inward somewhat toward each other. In some cases'this inward movement of the rods and collars 16, 16, may be lutilized to reduce the outwardly-actlng pressure of the springs 15, 15, or single spring) sufficiently to relieve the frictional engagement of the, chains 5, 5, with the beam-heads or ruiiles 4, 4, enough to permit the warp-beam to be turned conveniently by hand. In these cases, the pressure of the springs (or spring) will be reinstated and the friction thrown on again when the rods are caused to resume the .straight condition of Fig. 1. A special feature of the invention, however, consists in means for throwing-olf the friction by relieving the let-off levers from the effects of the spring tension without any material lessening of the tension of the spring or springs employed, and for throwlng the friction on again, the said means being arranged to operate without any loss or change of adjustment in either case. Figs. 1, 2, etc., show means for this purpose embodying the principle of combining with a'let-ofl lever, and its connections including an actuating spring, a stop which in the working position of the parts permits operation of the let-off lever by the spring, while by the throwingoff movement it is made operative to stop-off the spring by limiting the extent of the endwise expansion of the spring so as to prevent it from operating the left-off lever, and in addition, if desired, is inade operative to retract the let-off lever to reheve the frlction upon the beam-head or rutile. This means, in Figs. 1, 2, etc., comprises stop-collars 17, 17, mounted upon the portions of the rods 12, 12, that project outward beyond the collars or sleeves 11, 11, and fixed upon -such portions by means of clamping screws 11, in the working position shown in Fig. 1, v

so that the adjacent spring 15 is allowed to act expansively against the said coupling collar or sleeve 11 to 'actuate the corresponding let-ofi' lever to apply friction to the warpbeam. It also permits the let-olf devices to -accommodate themselves to any irregularities or eccentricity of a beam-head; in other words, in the relations of the parts which are illustrated in Fig. 1, the let-0E levers are controlled entirely by the elastic force ofy the springs, and are enabled to keep the friction-chains drawn tightly around the beamheads or rulles, as Well as to accommodate themselves to irre ularities of the beamheads or rules. When the rods are bent upward, they will draw inward through the coupling collars or sleeves 11, 11, until the stop-collars 17, 17 bring up against the outer ends of the said coupling collars or sleeves. As soon as this happens, the effect of springs 15, 15, in tending to turn the let-oli levers upon their pivotal supports or fulcra is stopped-off, i. e., neutralized, and the warpbeam is practically free to be turned by the weaver. This will be the case, regardless of the remaining degree of tension of the springs 15, 15, and even though in the position of the parts in Fig. 2 the springs 15, 15, still may be under compression giving them a length much shorter than the normal length of the springs. Continued bending of the rods upward will cause the stop-collars 17 17 to swing the let-oil' levers inward as in Fig. 2 so as thereby to slacken the friction-chains.

i The inward reaction of the two springs 15, 15, from the collars or sleeves 11, 11, 1n opposite directions relative to each other, tends to move the ,respective lengthwise inward toward each other. One effect of this is that when .the pivot 14 of the toggle is placed by the weaver in the locking position shown in Fig. 1, namely below a straight line extending from one collar or sleeve 11 to the other, the s rings act to keep it in such position, with e stop-shoulrods 12, 12,

' each other.

nasceva ders 137 13, on the respective flat heads 13, 13, of the two rods in stop-engagement with A further effect of the said inward reaction is that when the point of pivotal connection between the two .rods is lifted by the weaver above the said line, the inwardly acting pressure of the two springs,

reacting from the inner ends of collars or sleeves 11, 11, operates with a tendency to force the joined inner ends of the rods upward toward the position occupied in Fig. 2, and to kee them inthe latter position. The result wou d be the same if the spring were omitted from one rod and such rod locked to its collar or sleeve 11.

Bypreference, I employ springs 15, 15, which are highly resilient, light, and sensitive in respect to the letting-off action. In order to secure the required degree of outward pressure against the down-hanging arms of the let-olf levers in the working position of the parts shown in Fig. 1, such springs require to be of considerable length,

and to be compressed to a considerable eX- tent between collars 16, 16, and the collars or sleeves 11, 11. If such long springs were allowed to extend themselves fully in bending the rods upward, the.' joined inner ends of the rods would be thrown up too high toward the warp-beam. The stop-collars 17 17 however, by engagement with the coupling collars or sleeves 11, 11, limit-the inward movement of the rods relative to the said collars or sleeves, and the extent of the upward bending ofthe rods. These stops may be replaced b pins set in holes in the portions of the ro s which project outward beyond the collars or sleeves 11, 11, and to enable adjustment to be effected there may be a series of the said holes in each rod so that the pins may be shifted from hole to ho e. stop-collars 17 1 and fasten them in place by means of clamping screws 18, 18, which the direction of the length of the latter, to-

position of Fig. 2, and to permit the weaver to apply his foot to the upwardly bent rods for the purpose of pressing them down again into the position of Fig. 1.

When it is desired by the weaver to throw oi'l the friction, and he applies his foot or hand to lift the inner ends of the rods, the springs act as already described to force the Preferabl however, I employ the ermit them to be adjusted upon the rods in joined inner ends upward until the stopcollars 17 17, engage with the outer ends of the collars or sleeves 11, 11. A slight additional lift of the bent or broken toggle by the weaver to its position in Fig. 2 will draw the rods 12, 12, farther inward so as to cause the stop-collars 17 17, to act against the outer ends of the collars or sleeves 11, 11, to swing the down-hanging arms of the let-off levers inward and thereby rock the said levers so as to slacken the chains completely.

An important dierence between comparatively still springs such as may be employed in some cases, and the highly resilient, light and sensitive springs which I prefer, is the fact that in the case of the comparatively stiH springs a very small difference in the position of the adj listing collars 16, 16, will produce a marked variation in the tension and eect of such springs, whereas with the highly resilient springs, they are less affected by a small difference in the said position. It is therefore possibleto make a finer adjustment of the tension o the highly resilient springs.

Variations in the leverage are provided for by means of a series of holes 6a, 6a, Fig. 6, in each bracket 6, and a corresponding series of holes 9a, 9a, Fig. 8, in each of the let-oli levers, adapted to receive the fulcrum-pins 9, 9, for such levers. ABy removing a fulcrum-pin 9 from the holes in bracket and lever occupied by'it in Figs. 1, 2, 4 and 7, and shifting such pin into one of the other holes of the lever and into a cor responding hole in the bracket, the leverage in connection with such lever may be varied to increase or decrease the frictional action in proportion to the character of the goods being woven, or to variations in the diameter of the yarn mass upon the warp-beam. The fulcrum-pin is fastened removably by a clamping screw 6b in the hole in which it is seated in the bracket 6. To enable the leverage to`be varied still further, I make provision for shiftingthe points of engagement of the collars or sleeves 11, 11, with the vertical arms of the let-ofi' levers toward or from the'fulcra of the said levers. lFor this purpose I formin the down-hanging arm of each of said levers a series of slots 10a, 10a, at different distances from the fulcrum of the lever, to receive the pin which connects the corresponding collar or sleeve 11 with said arm. This permits meto shift the said collar or sleeve up or down upon the said arm so as to place it at the dlstance from the fulcrum of the lever which will give the required leverage and frictional action.

In ordinary practice the fulcrum-pin 9 of each lever is shifted to vary the action as found necessary for different weights of goods. The nut 16 is adjusted so as, at the outset, to compress the spring 15 to the ex- 40 slot, as in Figs. 9 and 10.

tent required by the diameter of the fullsized yarn-mass for the particular goods being woven. As the yarn-mass upon the warp-beam decreases in dlameter, the said nut is adjusted from time to time by the weaver so as to reduce the compression of the spring 15. Should these two adjustments prove insuficient, either to suit the welght of goods desired to be manufactured or to compensate for the varying dlameter of the yarn-mass, the collars or sleeves 11, 11, are shifted toward or fromthe fulcrum-plns 9, 9, to vary the leverage. As a convenient provision for removably connecting. a collar or sleeve 11 with the down-hangmg arm 10 of a let-oli'l lever, and holding 1t. securely engaged therewith while in the posltions. assumed by it in use, and at thesame time providing for ready disconnectlon at one point of the lever and re-connectlon at another, I form the slots 10, 10, 1n the shape of buttonholes, as in Figs. 1, 2 and 8, and

rovide the collar or sleeve 11 with a flat back 11, Fig. 9, to fit against the front surface of the said arm, and also provide it with a round stud-portion o1 pin 11b to lit in a rounded part of the buttonhole slot, and with a transversely projecting arm 11 at the end of the said cylindrical stud-portion or pin. In making application of the collar or sleeve 11 to the arm 10, the collar or sleeve is turned into a position which presents the arm 11 to the elongated ortion of the buttonhole slot. The arm an studportion or pin may then be passed through the slot. When the arm 11c is at the back of the arm 10, the collar or sleeve 11 is turned 'part Way around into its Working position, 1n which the arm 11 of the said collar or sleeve extends crosswise of, the buttonhole The engagement of.' the saidv arm 11c with the rear face of the arm 10 at oneV one side of the slot holds the collar or sleeve locked to the arm 10 without, however, interfering with the capacity ofthe collar 0r sleeve to swing or oscillate upon the stud-portion or pin 11" inl conformin to the various inclinations of the rod 12. gIhe rod 12 is then caused to extend through the collar or sleeve 11. While the rod occupies the collar or sleeve and the parts are in the positions shown in Figs. 1 and 2, the collars or sleeves cannot turn into position to become detached from the let-off levers.

Preferably, though not necessarily in all cases, the portion of a rod 12 `that plays within a collar or sleeve 11 is of rectangular or other non-circular cross-section, and the hole through the collar or sleeve 11 is shaped to fit such portion of the rod. This prevents therod from revolving within the collar or sleeve, and thereby the joint between'the connected rods is kept in position to swing in a vertical plane,l as required.

Other means of holding the rods 12, 12, from turning may be employcdin practice.

In Fig. 3 the construction is essentially the same as in Figs. 1 and 2, save that the rear girth19 of the loom-frame has attached thereto a downwardly-extending bracket 20 having a horizontal projecting portion or step 20a forming a stop for the joined heads 13, 13, of the rods 12, 12, when the connecting joint of the said rods is in its operative position. The stop shoulders 13, 13a, of Figs. 1, 2, 4 and 5 are omitted.

In some cases it is sufiicient, for the results desired in weaving, to employ a ir'ric-v tion chain in connection with one head only of the yarn beam, as shown in Fig. 11, Sheet 3. In order to enable me to slacken the chain at the other end of the yarn beam, or to completely remove such chain, I make provision for locking the let-011" lever at such end against movement so that it will serve' as a stationary support or carrier for the collar or sleeve 11 which is engaged therewith. This locking of the let-0H lcverlmaybe provided for in various ways whichl will be obvious to the skilled mechanic. I have herein shown each stand or bracket Gas having its outer face formed with a series of vertical grooves 6, 6c, Figs. 4 and 6,. Sheet 2, intersecting the pivot-holes 6a, 6, and the let-off lever as formed with corresponding ribs orprojections 8a, 8a, Fig. 4, adapted to enter the said grooves. When the lever is required to turn on its pivot or fulcrum-pin, as during the ordinary use thereof, a washer 9, Fig. 4 is mounted upon the fulerum-pin 9, between the grooved face of the stand or bracket and the rib or projection of the lever adjacent the hole 9a containing the said pin. This keeps `the ribs or projections of the lever out of engagement with the grooves of the stand or braclet, and the lever unlocked. The lever therefore is free to swing under the action 0f the springs and in response to strains on the Warps tending to occasion rocking ofthe Warp-beam. When, however, the lever is to be locked in fixed position, the washer 9c is removed and the lever is pushed close up against the stand or bracket so that the ribs or projections of the lever enter the grooves of the stand or bracket, as at the left in the plan view, Fig. 12. In such figure the washer 9 is shown mounted upon the outer portion of pin 9, between the let-oill lever and the head of the pin, merely for convenient safekeeping. I. have shown a groove in connection with each of the pivot holes of the stand or bracket, and a rib or projection in connection witheach'of the holes in the let-oi" lever for the fulcrum-pin, but as will be apparent a rib or projection out of the groove, in whichever pivot-hole the pin may be seated, 1s employed. That will be the fact in most cases.

F ig. 13 shows an embodiment of the leading Aprinciples of the invention in which I employ but one spring, 15, and one rod, 12, together with a special construction providing for throwing-off and throwing-on the friction. In. this embodiment the downhanging arm 10 of the let-off lever 8* at one side of the loom has swiveled thereto a collar or sleeve 21 receiving one end-portion of the rod 12a. This end-portion is .Screwthreaded and receives thereon nuts 22, 22, at opposite ends of the said sleeve or collar, whereby the rod is locked and secured against endwise movement with reference to the collar or sleeve. The spring 15a is confined between a collar constituted by a nut 16n on the said threaded portion of the rod and a sliding collar 23 upon the rod adja- I cent the other end thereof. This collar 23 is enga-ged with the let-off lever 26 at that side of the loom by means of a stud 24 with which'such collar is provided, entering and working within aninclined slot 25 in the down-hanging arm of the said let-0H lever.

26. The said slot 25 extends downward and inward toward the middle of the loom, and then is bent so as to form an offset or angular recess or notch, in which the said stud is held normally by the pressure of the eX- panding spiral spring 15a and thereby retained against tendency to upward movement within the slot. A stop-collar 17a is clamped by means of a screw 18t upon the end-portion of the rod which projects beyond the sliding collar. As in the case of the. construction shown in Figs. 1, 2 and 3, a short space of about one inch in practice is left between the outer end of the sliding sleeve or collar 23 and the said collar 17a, to allow the spring pressure to have full effect upon sleeve or collar 23, and permit play of the collar and spring to accommodate eccentricity and irregularities of the beam-head or ruiles. While the stud or pin 24 of the sliding collar 23 occupies the recess or notch at the lower end of the slot 25 in the let-oit' lever 26 at the right-hand side of the loom, a part of the pressure of the spring in expanding is transmitted to the downhanging arm of the said let-oil lever, and thereby the said lever is operated to tighten the friction chain upon the rutlie or beamhead at that. side of the loom. At the same time, the tendency of thespring to push the rod 12a in the other direction causes the said rod, through its enga-gement with the collar or sleeve 21 connected with the arm 10 of the let-ofiI lever 8b at the left-hand side of the loom, to apply pressure to the said letoti' lever 8b .so as to tighten the chain upon the ruiiie or beam-head at that side of the loom. Thus equal amounts of friction are applied to the opposite ends of the beam. When it is desired to throw ofi' the friction, the right-hand end of the rod will be lifted or struck upward by the weaver so as to discngage the pin 24 of the sliding collar 23 from the recess or notch at the lower end of the slot 25 in the let-0E lever 26. The said pin 24 thereupon will slide upward within the said slot, permitting the spring to eX- pand vuntil the sliding collar 23 is in engagement with the stop-collar 17a of the rod and theexpansive action of the spring thereby f:is limited, and relieving the let-off levers from pressure soas to permit them to swing toward each other, relaxing the frictionchains until the said levers hang loosely. If the right-hand end of the rod be raised still further by the weaver, the action of the pin 24 in sliding upward along the inner wall of slot 25 will draw the down-hanging arms of the let-ofi' levers closer toward each other, and thereby still further loosen the frictionchains. -To restore the friction, the rod is pressed downward by the weaver. The descent of pin 24 within slot 25 will operate to cause collar or sleeve 23 to be pressed inwardly, separating it from stop-collar 17, such separation permiting the spring 15PL to act elastically to exert pressure in the one direction through collar 16a, rod 12, and collar 21 to the left-hand let-olf lever, and in the other direction through collar 23 and pin 24 to the right-hand let-olf lever, causing the two let-0H levers to tighten the frictionchains and reinstate the friction. When pin 24 arrives at the lower end of slot 25 the tendency of the spring to expand will cause such pin to reenter the offset retaining notch at said lower-end, the notch however being shallow so that the collar 23 does not engage the collar 17 a.

In this construction, in the place of the stop-collar adjustably mounted upon the. outer end of the rod by means of a clamping screw, a small pin passed through one of a series of holes in the rod may be utilized as an adjustable stop.

In the case of each of the let-olf levers 8b and 26 of Fig 13 the samev provisions for adjustment of the pivot pin 9 to vary the leverage are made as in the case of the construction previously described. The same pro- In this construction the series of slots usual adjustments of the parts, and .when

the frictlon is on as in Fig. 13, is concentric or substantially so with the notch of lever 26 that is occupied by pin 24 of the sliding collar 23, so that the distance from each of the respective holes to said notch shall be substantially uniform. This renders it unnecessary to adjust the collars upon the rod 12n to compensate for a shift of the stud of collar 2l from one slot 10" to another'.

Fig. 14, Sheet 4, shows an embodiment of the invention in which at the left hand side the construction is the same as at the left hand side in Fig. 13, but the construction at the right-hand side providing for throwing-off and throwing-on the friction is different from that in Fig. 13. At the right hand side in Fig. 14 the sliding collar, 23, is formed at its underside with an enlargement containing an opening with downwardly Haring sldes to receive between them a stud 24a projecting from the down-hanging arm of the let-off lever 8 at said side of the loom. Normally the upper end of the opening or slot of the sliding collar rests upon the pin 24", and the spring 15" acts through the sliding collar and the engagement of the inner wall of the narrow portion of the said opening or slot at said upper end with said pin to actuate the said let-olf lever 8 to apply friction at the corresponding side Yof the loom, in addition to reacting upon the collar or nut 16a at the other end of therod 12 to move the rod endwise so as to actuate the let-oli lever 8" at the left-hand side of the loom as explained with reference to Fig. 13. When it is desired to relieve the tension and friction temporarily, the rod simply is lifted so as to raise the narrow portion of the opening or slot in the sliding collar from the stud carried by the let-oli" lever. This permits the collar to slide outward along the rod and upward along pin 24", relieving the let off levers of the springtension. The said collar moves outward upon the rod under the action of the spring in expanding until the sliding collar brings up against the stop-collar 17", which limits the capacity of the spring to expand. To restore the tension and friction, the rod is pressed down, the effect of the downward movement of the inner wall of the opening or slot of the collar 23a in contact with the pin 24a being to press the depending arm of lever 8 outward and the sliding collar 23a inward until the narrow portion of the said opening or slot passes down upon the pin. By this action the spring will be compressed, and its tension will be caused to operate the let-off levers to tighten the chains and apply friction to the warp-beam. The compression of the spring will allow the sliding collar 238L to separate from stop-collar 17a again, as in Fig. 14. The button-hole slots 10sl 10, in

' dle of the end with a retaining notch to receive andV the down-hanging arms of the two let-olf levers, provide for adjustment of collar or 'ltion with the collars or sleeves 11, 11, of

Figs. 1, 2 and 3.

Fig. 15, Sheet 4, shows an embodiment of the invention in which the sliding collar or sleeve, 23", is formed with a depending portion that is slotted to receive the-stud 24" carried by the lever 8. The slot, 27, inclines downwardly and inwardly toward the midloom, and is formed at its upper retain the said stud in the working position and relation of the parts. While the notch is occupied by the pin the spring is maintained in a state of compression, and operates the let-oli levers to roduce the required friction upon the hea s or ruies of the warp-beam. When it is desired to relievethe let-ofi'l levers of the effect of the spring, and thereby relieve the frictional resistance to the turning of the warp-beam, the rod is raised by the weaver so as to lift the retaining notch off the pin 24". This permits the collar to slide outward along the rod, and in doing so its slotted portion slides upward upon the pin 24", the joint effect of which is to relieve the let-off levers of the springtension. The spring expands until it slides the collar outward into engagement with stop-collar 17". If the rod be further raised by the weaver, the outer wall of slot 27 will operate against pin 24" so as to cause drawn toward each the let-ofi'l levers to be other and further slacken the frictionchains. When it is desired to restore the friction, the rod is pressed down by application of the weavers foot, or otherwise. As the inclined inner wall of the slot 27 slides down at the inner side of pin 24",.the cam-action of said inclined wall causes the collar 23" to slide inward upon rod 12", compressing the spring 15a and separating said collar from stop-collar 17a until the said pin renters the retaining notch.

Fig. ,16, Sheet 5, shows in rear elevation an embodiment of the invention having a further modification of the means for throwing-off the effect of the spring in which a rotatable cam constitutes an element of the said means. Fig. 17 is a partial lan of the parts represented in Fig. 16.

igs. 18, 19 and 20 are views showing on an enlarged scale the details of the throwin off means. In these figures the let-off lever 8 at the right-hand side of the loom corresponds with the let-off lever at the same side in-Figs. 1, 2 and 3. The rod and spring, and theparts at the left-hand side of the loom, are the same as in The collar or sleeve 23c which is connected Figs. 13, 14, and 15.

relations of the with the said right-hand let-oli lever 8, and mounted upon the righ -hand end-portion of the rod 12a, has its outer end formed with an inclined or beveled cam-face for co-action with the corresponding but reversely inclined or beveled cam-face of the inner end of the throwing-oli cam 28. The said cam is sleeved upon the outer portion of the rod 12a beyond the collar or sleeve 23 so as\ to be capable of turning around the rod. Its outer end is also furnished with a cam-face inclined or beveled in the same direction as the cam-face of the outer end of collar or sleeve 23, to co-act with the inclined or lbeveled cam-face of the inner endof a collar 29 that is made fast upon the outer extremity of the rod 12a by means of a clamping screw 30. The throwing-ofi' cam 28 is furnished with an operating handle 28u by means of which it may be manually turned upon the rod 12a. The normal positions and parts are as represented in Figs. 16, 17 and 18. In these views the handle 28a extends toward the front of the loom, and the inclined cam-faces of the opposite ends of the throwing-oil' cam are parallel with those of the adjacent ends of the sliding collar 23c and the fixed collar 29. Suliicient play is left between the throwingoli" cani and the two collars to ermit the spring 15a to expand fully to the extent required for operating the let-0H levers to produce the required friction. When it is desired to throw-oli the eect of the spring, and thereby relieve the warp-beam of friction, the weaver takes hold of the handle 28 and swings it rearward so as thereby to cause the throwing-olii' cam to make a halfturn, giving the saidcam the position occupied by it in Figs. 19 and 20. In the turning movement of the cam its inclined camfaces. act against the cam-faces of the sliding collar 23c and fixed collar 29 to separate such collars from each other. Thus the cam acts to take up all play or looseness between the said collars, in addition to moving them oppositely so as to swing the vertical arms of the opposite let-off levers toward each other, thereby moving the let-off levers so as to slacken the chains 5, 5, in addition to taking the tension of the spring oli' the let-off levers. In order to enable the throwing-oli cani to remain in the position occupied by it in Figs. 19 and 20 without tendency to return to its former position, thev prominent portions or projections of the said cam and of the collars 23 and 29 are attened, so that when the flattened surfaces are in engagement with each other the pressure of the parts against one another has no tendency to cause the throwing-oil' cam to turn.

Figs. 21 and 22, Sheet 6, show the invention embodied in connection with a compound-lever arrangement, the details of which are illustrated in Figs.'23 .to 32, Sheet link, so as to give 7. Fig. 23 is a rear elevation of the parts at; the left-hand side of the loom, omitting the stand 61, with the connections between the lever-system and the rod 12EL shown partly in section. Fig. 24 is an end elevation of such parts. Fig. 25 is a plan view thereof, including the said stand 61. Fig. 26 is a plan view of lever 81. Figs. 27 to 32 show parts separately. This arrangement comprises a pair of levers 81, 82, at each side of the loom. The chain 5 at each side of the loom is engaged with a hook 7 that is connected with one arm of the lever 81 at such side, the said lever being horizontally disposed and mounted upon a pivot 9 upon the supporting stand 61. To permit adjustment of the leverage of the said lever, the said stand and the said lever have, respectively, as shown best in Figs. 23, 25 and 26, two hubs and holes for the reception of the pivotpin or stud 9. The said adjustment is effected by a shift of the said pivot-pin or stud from one hole inl the lever andstand to the other. The lever 82 is mounted by a pivot 91 upon the stand 61, the said lever 82 having an outwardly extending horizontal arm 82x which engages with the under side of the outwardly extending arm 81a of the first lever, the said second lever having also a downhanging' arm. The downhanging arms of the levers 82, 82, at the two sides of the loom are connected by means of deyices including a rod 12a, a spring 15a, a sliding collar 11d upon said rod engaging with the lever 82 at the right-hand side of the loom, la stop-collar 172L upon the end-portion of the rod beyond the sliding collar 11d, and connections, presently to be described, between the left-hand end of the rod and the lever 82 at the left-hand side .of the loom. The tendency of spring 15a to expand causes such spring to actuate the levers 81, 81, to draw the friction-chains tight around the heads or ruiiles of the warp-beam. The devices which connect the rod 12a .and the lever 82 at the left-hand side of the loom are contrived to provide for throwing-off and on the friction. They operate on avsomewhat different principle from any of the arrangements which have thus far been described. The left-hand end of the rod 12a is engaged by a rigid connection *with a block 31 which constitutes in, effect a head for the said end of the rod. A link 33, shown separately in end elevation in Fig. 28 and in plan in Fig. 29, connects the block 31 with the downhanging arm of the adjacent lever 82. The link is swiveled to the said arm of the lever 82 by means of a stud 34 projecting from the outer end of the i the link capacity for swinging movement in vertical plane. The

link is engaged with the block by means of a stud entering and fitting a hole in the block. The block 31 is retained upon the pivot stud 32 by means of a screw 31a occupying a threaded hole in the block and entering by its tip into a groove 32*l around the said stud. The described mode of connection between the block and the link permits them to swivel or turn relative to each other in a vertical plane. In the working relations of the parts, as shownin-Figs. 21, 22, 23 and 25, the link-33 is inra straight line with the rod 12n and its head block 31. This gives the maximum effectivelength of the connection-members 12a, 21 and 33. For the purpose of enabling the said parts to be locked in the said straight line with one another s\o as to prevent the link and block from turning 'relative to each other around the connecting stud 32, the block 31 has a slot or notch 31h formed in its outer end, shown best in Fig. 27, and with the link 33 is combined a locking piece 35, shown separately in plan in Fig. 30, having an eye 35a tol receive the stem of a'pin 36,'shown separately in Figs. 31 and 32, which connects the locking piece pivotally with the link. The said locking piece is furnished with a locking-pin or projection 35b which, when the link and enters the slot or notch 31b at the.

locking-piece 1s swung from its unlocking position in Figs. 23, 24C and 25, around into the locking position shown in Figs. 21 and 22, Works through a slot 33, Fig. 23, in the' outer end of the block 31, when the block and the link are in the same straight line,` as in Fig. 22. So long as the locking-pin or projection 35b occupies the notch or slot 31? the link and block are locked together so that the link constitutes in eect a rigid continuation of the rod l2a and serves to transmit the pushing pressure of the spring 15a to the adjacent lever 82. See Figs. 21 and 22. At the same time the reaction of the spring against the sliding collar 11d operl ates to transmit an equal amount of pressureto the opposite lever 82.4 When it is desired to throw-ofi1 the friction, the locking-piece 35 is swung rearwardly yso as to withdraw its pin or projection 35b from the notch 31b of the block 31 and the slot 33a of the link. This renders the link and block free to turn relative to each other around the connecting-stud 32. If the connectingstud 32 is not already located above a straight line extending from the pivotal point 34C to the point of pivotal connection between the collar lld'and the opposite lever 82, it may be raised by the weaver, `for which purpose he may` if he desires use the pin or projection 35b as a handle. The raising however may be effected by the weaver by taking hold of the rod or link at any point. With the'point 32 of pivotal connection above the said straight line, and the parts unlocked as described, the spring 15a is free to occasion endwise movement of the rod 12a toward the left, thereby turning the .ward each other, friction-chains, the entire mechanism assuming ythe relaxed condition shown in Fig. 33.

income link outward upon its point 34of pivotal engagement with the left-hand lever 82, permitting the rod and link to double up uponv 'reducing their efother, therebyre'leasing the levers 81, 8l, so

as to permit the chains 5, 5, to slacken. Another result is to permit of relative sliding movement of the rod 12a respect to eachother until the said., collar 11d and the stop-collar 17*L engage with each other as in Fig. 33, thereby stopping-oli'l the expansion of the spring. and depriving it of the power to further actuate the let-ofi levers. If now the Weaver, jection 35" as a handle, swings the locking member and link 33 farther tothe left, the effect will be to swing the downhanging arms of the :levers 82, 82, inward closer tostll further slackening the When it is desired to restore the friction, the link 33 is swung by the weaver over inward and down from its posltion in Fig..33 to that levers to tighten the friction-chains'anew, and then the parts are again locked by swinging the locking-piece 35 upon its pivotal connection in Figs. 21 and 2.2, so as to cause its pin or projection 35b to pass through the slot 33a of the link and into the notch 31b at the outer end of the block 31. This restores the general mechanism to the condition shown in Fig. 21, and locks the block and rod and the link in their working relations so as to maintain the spring eective.

It is necessary that in turning the link from its positionin Fig. 33 t0 that in' Figs. 21 and 22,l as just explained, the point of connection between such link and the block 31 should not be caused to pass down below the straight line connecting the points of pivotal connection with the lower ends of the two let-off levers 82, 82. For this urpose I provide a lip 33, Figs. 25 an 29, upon the link, which by striking upon the top of the block limits the vdownward movement of the link relative to the block. It is important that the locldng piece, when in position to lock the link and the block in working relations, should itself be locked so as `to prevent it from accidentally becoming jarred or knocked into unlocking position. For this purpose the pin 36 which pivots the said lookin piece to the link is furnished with a feat er 36a, Figs. 31 and 32, on one side thereof, and the upper ear of the two ears on the link between which the locking piece is mounted is furnished at one side of the hole 33d therethrough (Fig. 29),*with a notch 33 in which the said feather 36a is and collar 11d with 1n Figs. 21, 23 and 25. This operates the 

